Method of and apparatus for generating a frequency modulated ultrahigh frequency radio transmission signal
US4710970A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 11, 1985 |
| Grant date | Dec 1, 1987 |
| Priority date | — |
| Expiry date | Sep 11, 2005 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03C2200/0079
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A UHF transmission frequency oscillator generates a UHF radio signal that is frequency modulated by a program signal. The voltage applied to a control voltage input of the UHF transmission frequency oscillator controls the transmission frequency. A sample of the UHF transmission frequency signal is heterodyned with the output of a crystal controlled reference frequency oscillator to generate a frequency difference signal. A voltage controlled VHF radio signal generator produces a VHF signal frequency modulated by the program signal. A phase detector receives the frequency difference signal and the VHF signal frequency modulated by the program signal and therefrom applies a voltage to the control voltage input of the UHF transmission frequency oscillator for the transmission of a UHF radio frequency signal frequency modulated by the program signal. The VHF voltage controlled generator has VHF programmable frequency dividers, which are pre-settable, to establish the VHF radio transmission frequency. The output of the VHF voltage controlled generator is phase locked through the phase detector with the crystal controlled reference oscillator for the stabilizing of the output transmissi…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.